In the following, “operation in unitary mode” or “operation in tube-by-tube mode” are intended to mean a mode of operation in which the blood samples to be analysed are passed one after another, i.e. tube by tube, without the assembly of these tubes in cassette-type supports or the like.
By the expression “analysis of whole blood”, it is intended to designate an analyser carrying out analyses on whole blood, i.e. containing all the elements of blood, as opposed to analysers operating on plasma or serum. Cell counters form part of whole blood analysers but the invention is not limited to only cell counters.
The expression “quality control” is used to mean a procedure which consists in checking at least daily that the analyser is working properly before carrying out analyses of blood samples from patients.
There are different types of blood analysers which carry out various types of analysis, including optical, physico-chemical analyses etc. on blood samples and which then automatically issue the results of analysis.
An essential condition for the correct functioning of these analysers is that the blood tubes have been previously correctly stirred during a stirring phase which precedes analysis.
In blood analysers operating in unitary mode or tube-by-tube mode, this stirring phase is often carried out manually, therefore in a more or less haphazard manner.
Consequently, when the user of the blood analyser is not familiar with laboratory practice, this preliminary phase of stirring may be carried out incorrectly, which may distort the results of the analysis.
This is often the case when the users are not specifically trained in laboratory practice.